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Signed-off-by: Krasi Georgiev <8903888+krasi-georgiev@users.noreply.github.com>

pkg/query/iter.go

@@ -582,6 +582,7 @@ func (it *dedupSeriesIterator) Next() bool {
 	// Advance both iterators to at least the next highest timestamp plus the potential penalty.
 	if it.aok {
 		it.aok = it.a.Seek(it.lastT + 1 + it.penA)
+		// When A is exhausted the seek for B below should be without any penalty
 		if !it.aok {
 			it.penB = 0
 		}